Fish
Plains Killifish
Fundulus zebrinus · also called plains killifishes
In a wide, shallow prairie stream where the water barely covers its back, a plains killifish suddenly vanishes into the sandy bottom, burying itself to escape a passing predator in one of the more exposed, unforgiving stream habitats any small fish has to survive.
Overview
The plains killifish, Fundulus zebrinus, is a small, hardy fish native to wide, shallow, sandy-bottomed prairie streams across a broad range of the central Great Plains. Its distinctive sand-burying escape behaviour, bold vertical barring, and strong tolerance for the naturally harsh and variable conditions of prairie rivers make it one of the better-adapted native fish for one of North America’s most exposed freshwater habitats.
A fish that disappears into the riverbed itself
Rather than relying on speed or cover alone, the plains killifish’s ability to bury itself directly into loose sand gives it an escape option perfectly matched to the wide, shallow, largely coverless streams it calls home.
Status
Least Concern — widespread and common across suitable sandy prairie stream habitat throughout the central Great Plains.
Plains Killifish: common questions
Why does the plains killifish bury itself in sand?
This species can bury itself in loose, sandy streambed sediment, a behaviour that helps it escape predators and avoid extreme water temperatures within the shallow, exposed prairie rivers it inhabits, offering a level of protection that swimming alone could not provide in such open, shallow habitat.
How does the plains killifish survive such harsh prairie stream conditions?
This species tolerates the naturally variable flow, temperature, and salinity typical of shallow prairie streams, conditions considerably harsher and less stable than the habitat many other fish species require, an adaptation that lets it thrive across the Great Plains where more sensitive fish species could not persist.
How can you identify a plains killifish?
Look for bold, vertical dark barring along the sides of the body, a distinctive pattern reflected in the species' scientific name and useful for distinguishing it from other small fish sharing the same sandy prairie stream habitat.
Where does the plains killifish live?
This species is native to wide, shallow, sandy-bottomed prairie streams across a broad range of the central Great Plains, staying closely associated with this specific type of shifting, sand-bottomed river habitat throughout its range.